The present invention relates in general to data buffers and in particular to a multiple port data buffer configurable by externally generated commands for interfacing a host computer to equipment modules using various types of input and output ports and data communication protocols.
in a telephone network, equipment modules such as telephone and data switches, voice and data multiplexers and carrier equipment typically include one or more serial RS-232 ports. These ports provide outputs for alarm, status or statistical reporting or provide inputs for equipment configuration commands and data. Unfortunately the RS-232 standard allows variation in port configuration wherein ports of various telephone equipment modules employ differing word sizes, baud rates, error checking schemes, data flow control codes, etc. In addition, some equipment modules are controlled by parallel input signals and generate binary output signals for alarm or status reporting. While it is desirable to centralize the tasks of monitoring and controlling the various equipment modules in a single host computer, variation in module input/output configuration complicates the task of interfacing the host computer to the various equipment modules.
Centralization is further complicated in that alarm and statistical data output of many equipment modules must be captured at the port output. When generated or it is lost. Therefore, a centralized host computer acquiring alarm data from many equipment modules must poll all the maintenance ports quickly to avoid missing alarm data. While a high speed host computer may be capable of polling equipment modules rapidly enough, such a host computer is usually large and expensive.